#include <iostream>

using namespace  std;
namespace ns1 {
	void func(void) {
		//std::cout << "ns1::func" << std::endl;
		cout << "ns1::func" << endl;
	}
}
namespace ns2 {
	void func(void) {
		//std::cout << "ns2::func" << std::endl;
		cout << "ns2::func" << endl;
	}
}
int main (void)
{
	//func(); error
	using namespace ns1;
	func(); //ns1::func
	using namespace ns2;
	ns2::func(); //ns2::func //error 歧义错误
	return 0;
}
